Sustainability: Scrap Wrappers

What kind of bag can be used to collect kitchen scraps for tossing them in the green bin? This is a question that has been floating around our town since our waste hauler EDCO implemented curbside green waste collection in Del Mar in July 2022, in compliance with California State Bill 1383.

Below are a few facts to approach the multifaceted question:

• The commingled green waste composed of yard cuttings, soiled paper, and kitchen food scraps is processed at EDCO’s anaerobic digester facility in Escondido. The anaerobic digester cannot process plastic bags that are labeled compostable or biodegradable. Compostable bags require oxygen while anaerobic digestion does not. Anaerobic digestion involves steady agitation and a 131° Fahrenheit environment that “digests” green waste and food scraps without oxygen. Hence, a certified compostable bag is not compatible with EDCO’s process. A certified compostable or biodegradable bag might work for your backyard composting bin.
• Items that do not belong in the anaerobic digester are considered “contaminants” and are manually removed by workers. Metals are removed by a giant magnet! Using a bag that might or might not be compatible with the anaerobic digester will most likely require additional labor to remove it.
• In addition to the methane that becomes renewable natural gas powering EDCO’s trucks, the physical output of the digester is a substance called digestate, which is distributed to local farmers for use as ground cover. Therefore, it is to everyone’s benefit to avoid contaminants in our green bins.
• There is no rule requiring kitchen scraps to be bagged before adding them to the green bin. The EDCO-provided kitchen caddy can be cleaned in the dishwasher. Customers can request a complimentary caddy on EDCO’s website.
• If you feel strongly that using a bag is necessary, why not reuse a paper bag from the grocery or the produce aisle? How about reusing newspapers such as the Del Mar Times to line the kitchen caddy, once you are done reading it?
• If you are ready to pay over $1 per bag, the Bag to Earth and the All-Green caddy liner sold on Amazon are compatible with EDCO’s digester.

While we see the market flooded with compostable and biodegradable plastic bags made out of corn or wheat or proprietary mixtures, such as Mater-Bi®, and certified to biodegrade in a few months, our Del Mar reality is such that they just won’t work with our local waste hauler’s method of anaerobic digestion. Let’s go on the cheap and use newspaper lining if we must.